In the building construction industry metal framing assemblies are commonly used to construct commercial and residential buildings. Such metal framing assemblies are generally constructed from a plurality of metal framing members including studs, joist, trusses, and other metal posts and beams formed from sheet metal and frequently fabricated to have the same general cross-sectional dimensions as standard wood members used for similar purposes. Metal framing members are typically constructed by roll-forming 12 to 24 gauge galvanized sheet steel. Although many cross-sectional shapes are available, the primary shapes used in building construction are C-shaped studs and U-shaped tracks.
In the building construction trade, a head-of-wall joint (also sometimes referred to as a top-of-wall joint) refers to the linear junction or interface existing between a top section of a framing/wallboard wall assembly and the ceiling (where the ceiling may be a next-level floor or corrugated pan roof deck, for example). In common practice, a wall to ceiling connection of many newly constructed buildings consists essentially of an inverted U-shaped elongated steel channel (or track) configured to receive steel studs between the legs (also sometimes referred to as sidewalls or flanges) of the shaped channel. A wallboard is generally attached to at least one side of the studs. The studs and wallboard are in many instances spaced apart from the ceiling a short gap distance in order to allow for ceiling deflections caused by seismic activity or moving overhead loads. Similarly, wallboard is also commonly horizontally spaced apart as short gap distance from an immediately adjacent piece of wallboard (to thereby allow for thermal expansion and/or contraction of the wallboard without visible wall cracking). Exemplary steel stud wall constructions may be found in U.S. Pat. Nos. 4,854,096 and 4,805,364 both to Smolik, and U.S. Pat. No. 5,127,203 to Paquette. Exemplary dynamic head-of-wall systems having steel stud wall constructions may be found in U.S. Pat. No. 5,127,760 to Brady, and U.S. Pat. No. 6,748,705 to Orszulak et al.
In order to contain the spread of smoke and fire, a fire resistant material such as, for example, mineral wool is often times stuffed into the gaps between the ceiling and wallboard. For example, mineral wool is often stuffed between a steel header beam (e.g., an elongated U-shaped channel) and a corrugated steel roof deck (used in many types of steel and concrete building constructions); a fire resistant and generally elastomeric spray coating is then applied onto the exposed mineral wool to thereby form a fire resistant joint seal. In certain situations where the ceiling to wallboard gap is relatively small, a fire resistant and elastomeric caulk is commonly applied so as to fill any small gaps.
Intumescent materials have been used to seal certain types of construction gaps such as, for example, conduit through-holes. In this regard, intumescent and fire barrier materials (often referred to as firestop materials or fire retardant materials) have been used to reduce or eliminate the passage of smoke and fire through openings between walls and floors and the openings caused by through-penetrations (i.e., an opening in a floor or wall which passes all the way through from one room to another) in buildings, such as the voids left by burning or melting cable insulation resulting from a fire in a modern office building. Characteristics of fire barrier materials suitable for typical commercial fire protection use include flexibility prior to exposure to heat, the ability to insulate and/or expand, and the ability to harden in place upon exposure to fire (i.e., to char sufficiently to deter the passage of heat, smoke, flames, and/or gases). Although many such materials are available, the industry has long sought better and more effective uses of these materials and novel approaches for better fire protection, especially in the context of wall construction joints and gaps.
Among the few products and methods available for effectively and efficiently sealing head-of-wall construction joints and gaps (to thereby significantly enhance the ability of such joints and gaps to withstand smoke and fire penetration) are those sold under the tradename BLAZEFRAME, which products are protected under U.S. Pat. No. 7,681,365, U.S. Pat. No. 7,814,718, U.S. Pat. No. 7,866,108, and U.S. Pat. No. 8,056,293 all to Klein. In particular, the BlazeFrame line of technology addresses the need for adequate fire protection of dynamic head-of-wall systems associated with steel stud wall constructions.
Although advances have been made with respect to fire protection of structural wall assemblies, there is still a need in the art for new and improved structural wall assemblies and related components, especially in terms of products that allow for expansion and/or contraction of opposing pieces of wallboard fastened onto a wall assembly, while at the same time allowing for adequate fire protection. The present invention fulfills these needs and provides for further related advantages.